Improvement in tube-cutters for oil-wells



Patented. Aug. 14.1877.

N.FEYEHS, PHOTO LITHDGRAPHER NASMINGTON D C -#ITED?*STATE-SY PATENTDEF-ICE.

HART HARRIs, or PETROLIA, PENNSYLVANIA.

IMPROVEMENT IN TUBE-CUTTERSF OR OIL-WELLS- Specification forming part ofLetters Patent N o. [94, 149, dated August 14, 1877 application filedJune 20, 1877.

To all whom it may concern:

Be it known that I, HART HARRIS, of Fetrolia, Butler county,Pennsylvania, have invented an Improvement in Tools for Cutting Casingsin Oil or Artesian Wells; and I do hereby declare the following to be afull and 4 a view showing the bottom of one of the cutter-carriages.

My invention relates to that class of tools used in cutting the casingsin Artesiau or oil wells, so that said casings may the more readily bedrawn from the base when it may be necessary to repair or removethem.

My invention consists in providing a cutting apparatus with a partlysquare and partly tapering mandrel, by which the cutters may be revolvedwithin the casing and forced out so as to sever the casing at anydesired point, the whole apparatus being held imposition by acentering-head provided with friction pressure-rollers.

In the drawings, A is a friction centeringhead, carrying four or morefriction-rollers, a a a a, within sockets upon its sides. The rollersare preferably elliptical in form,'and revolve in hearings in slidingcarriages b b, forced outward by the springs c c. The frictioncentering-head A is perforated longitudinally by a square hole, d, andhas at each end of square hole (1 notches e e e e, also forming a squaredepression concentric with the square hole. B is a cutter-head, carryingfour or more hardened cutters, f f f f, within sockets upon its sides.The cutters are round and sharpened to a blunt edge,and are journaled insliding carriages h hit it, traveling loosely in the sockets, and keptin a horizontal position by a spline, t. Upon the inside face of thecarriages h is a conical groove, k, Fig.4, hereinafter referred to.Thecutter-head Bis perforated by a longitudinal hole of tapering shape,the side diverging downward. The friction centering-head A and cutter Bare secured together by a piece of metal tubing.

0 is a mandrel, coupled to a rod or tube at its upper end by a coupling,as at l. The

length ofthe mandrel G is divided into four sections, m n 0 p. The firstsection, m, is round and small enough to pass through the square hole dof the friction centering-head A, and longer than said hole cl. Thesecond section, a, is square, and of a size to easily pass through thesquare hole (1, and readily drop into the notches e e e e at either endof the friction centering-head A. The third section is again round,similar to section m, and about the same length. Section 1) is conicalin shape, increasing in size toward the lower end, where it terminatesin a head or collar.

The operation of my device is as follows: The mandrel 0 being dropped toits lowest position, as in Fig. 2, and the upper portion of the squaresection a drawn within the notches es, the apparatus is ready to belowered into the casing until the knives f reach the place to be cut.The mandrel C, after having been lowered sufficiently to be releasedfrom the notches e, is turned one-eighth of a revolution, when thesquare section it can be raised through the square hole at, drawing theconical section p through the conical grooves k in the backs of thecutter-carriages h, forcing the cutters against the inner surface of thecasing. As the mandrel is raised it may be revolved, carrying thefriction centeringhead and cutter-head with it, the cutters f beingforced into the casing. When the square section a has passed through thesquare hole d, it may receive one-eighth of a revolution again, and bedropped in the notches e, as seen in Fig. 1. When it is necessary toremove the tool from the casing, or

-to out another part of it, the mandrel G is raised a little, and, afterreceiving one-eighth of a revolution, may be dropped through the squarehole d. The cutters having receded, the tool may be withdrawn from thecasing.

Having thus fully described my invention, what I claim, and desire tosecure by Letters Patent, is-

l. The cutter-head B, the knives of which are operated by a conicalmandrel, O, in combination with a separate friction centeringhead,substantially as described.

2. A cutter-head and conical mandrel, said mandrel having a squaresection upon its shank. in combination with a friction centeri n g-headhaving a rectangular bore, substan- The above specification of mysaidinvention tially as described. signed and witnessed alt Petrolia,this 22d day 3. The square section n of the mandrel O, of May, A. D.1877. r

in combination with the friction-head A, having notches e e e e ateither end, substantially HART HARRIS. as described.

4. The friction. centering head A, provided Witnesses: with yieldingfriction-rollers, in combination 0. M. VOORHIES, with a cutter-head,substantially as described. THOMAS DALTON.

